1. Field of the Invention
The present invention relates to differentiated service in a computer communications network and more particularly to end-to-end (e2e) service level agreement (SLA) compliance.
2. Description of the Related Art
The modern global network can be viewed as a complex interweaving of multiple network technologies, server platforms, client capabilities and application requirements. The vast majority of network technologies handle device requests indiscriminately. That is, regardless of the identity of the requestor or the type of request, each device request can be processed with equal priority. Given the exponential increase in network traffic across the Internet, however, more recent network-oriented computing devices have begun to provide varying levels of computing services based upon what has been referred to as a “policy based service differentiation model”.
In a policy based service differentiation model, the computing devices can offer many levels of service where different requests for different content or services which originate from different requestors receive different levels of treatment depending upon administratively defined policies. In this regard, a service level agreement (SLA) can specify a guaranteed level of responsiveness based upon a pre-defined policy. More particularly, the SLA is a contract that specifies an agreement between a service provider and customer regarding a level of service to be provided by the service provider to the customer in respect to a specific resource.
Within the modern enterprise, the enterprise can receive a substantial benefit for effectively providing differentiated service to different customers and different data so that some customers and data receive a higher level of service than other customers and data on the network. That is to say, where the enterprise satisfies the expected service level of a valued customer, the enterprise can retain the customer. Conversely, where the enterprise fails to satisfy the expected level of service of a valued customer, the enterprise likely can lose the customer. Hence, differentiated service can be an important component of e-commerce inasmuch as a customer always can be viewed as merely “one click away” from a competitor's system where response times falter.
Accordingly, the enforcement of the terms of an SLA can be of paramount importance in managing the customer service relationship. To that end, service level management systems have become commonplace in the enterprise. A service level management system can track services provided to customers and compare the delivery of services to the service terms of a corresponding SLA. Performance metrics can be collected over time in respect to the resources associated with the SLA and the metrics can be evaluated to determine if any of the terms of the SLA have been violated.
The application of an SLA to a manageable network involves the tuning of the elements of the manageable network to achieve the performance guaranteed by the SLA. Generally, the performance guaranteed by an SLA relates in some way to an acceptable average delay demonstrated by the manageable network. In an end to end (e2e) network environment, however, the communications path between two endpoints can traverse both manageable portions of a network and unmanageable portions of a network. As such, tuning the components of the e2e network environment necessarily is limited to a best guess approach to providing extremely conservative restraints on the manageable portion of the e2e network and a loosing of terms in a corresponding e2e SLA.